Subj : HVYSNOW: Probabilistic He
To   : All
From : Mike Powell
Date : Wed Apr 17 2024 08:26:00

FOUS11 KWBC 170715
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
315 AM EDT Wed Apr 17 2024

Valid 12Z Wed Apr 17 2024 - 12Z Sat Apr 20 2024


....Northern Rockies...
Day 1...

A positively-tilted trough over Montana early this morning digs
southeastward into Wyoming into this evening. Post- cold frontal
upslope on surface northerly flow and the left- exit region of a
110kt NWly jet will further add lift over southwest MT and
northern WY. Snow, moderate at times, will continue over the
Absarokas around Yellowstone and the Bighorns through today with an
additional 6-12" at higher elevations. Snow levels in these areas
will drop to around 4000ft today. Later tonight the parent low over
the Canadian Prairies will shift east, moving the northern Rockies
into the left- entrance region of the jet allowing rapid weakening
snow in the Rockies.


....Central Rockies...
Day 3...

The combination of high pressure building down the northern Plains
providing an upsloping easterly component to cold low level flow,
moisture streaming up the southern Plains, and lift in the right
entrance region to a jet stream over the central Plains looks to
allow snow bands to develop over southern WY and/or northern CO
Friday night. As of now these bands may reach moderate intensity
and spill from the mountains onto the High Plains. This will need
further monitoring.


The probability of significant icing is less than 10 percent.


Jackson


$$
--- SBBSecho 3.20-Linux
 * Origin: ILink: CCO - capitolcityonline.net (454:3/105)

.